xref: /dragonfly/sys/net/route.c (revision 7485684fa5c3fadb6c7a1da0d8bb6ea5da4e0f2f)
1 /*
2  * Copyright (c) 2004, 2005 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Jeffrey M. Hsu.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of The DragonFly Project nor the names of its
16  *    contributors may be used to endorse or promote products derived
17  *    from this software without specific, prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
23  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1980, 1986, 1991, 1993
35  *        The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *        @(#)route.c         8.3 (Berkeley) 1/9/95
62  * $FreeBSD: src/sys/net/route.c,v 1.59.2.10 2003/01/17 08:04:00 ru Exp $
63  */
64 
65 #include "opt_inet.h"
66 #include "opt_mpls.h"
67 
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/malloc.h>
71 #include <sys/mbuf.h>
72 #include <sys/socket.h>
73 #include <sys/domain.h>
74 #include <sys/kernel.h>
75 #include <sys/sysctl.h>
76 #include <sys/globaldata.h>
77 #include <sys/thread.h>
78 
79 #include <net/if.h>
80 #include <net/if_var.h>
81 #include <net/route.h>
82 #include <net/netisr.h>
83 
84 #include <netinet/in.h>
85 #include <net/ip_mroute/ip_mroute.h>
86 
87 #include <sys/thread2.h>
88 #include <sys/msgport2.h>
89 #include <net/netmsg2.h>
90 #include <net/netisr2.h>
91 
92 #ifdef MPLS
93 #include <netproto/mpls/mpls.h>
94 #endif
95 
96 static struct rtstatistics rtstatistics_percpu[MAXCPU] __cachealign;
97 #define rtstat      rtstatistics_percpu[mycpuid]
98 
99 struct radix_node_head *rt_tables[MAXCPU][AF_MAX+1];
100 
101 static void         rt_maskedcopy (struct sockaddr *, struct sockaddr *,
102                                      struct sockaddr *);
103 static void rtable_init(void);
104 static void rtinit_rtrequest_callback(int, int, struct rt_addrinfo *,
105                                               struct rtentry *, void *);
106 
107 static void rtredirect_msghandler(netmsg_t msg);
108 static void rtrequest1_msghandler(netmsg_t msg);
109 static void rtsearch_msghandler(netmsg_t msg);
110 static void rtmask_add_msghandler(netmsg_t msg);
111 
112 static int rt_setshims(struct rtentry *, struct sockaddr **);
113 
114 SYSCTL_NODE(_net, OID_AUTO, route, CTLFLAG_RW, 0, "Routing");
115 
116 #ifdef ROUTE_DEBUG
117 static int route_debug = 1;
118 SYSCTL_INT(_net_route, OID_AUTO, route_debug, CTLFLAG_RW,
119              &route_debug, 0, "");
120 #endif
121 
122 u_long route_kmalloc_limit = 0;
123 TUNABLE_ULONG("net.route.kmalloc_limit", &route_kmalloc_limit);
124 
125 /*
126  * Initialize the route table(s) for protocol domains and
127  * create a helper thread which will be responsible for updating
128  * route table entries on each cpu.
129  */
130 void
route_init(void)131 route_init(void)
132 {
133           int cpu;
134 
135           if (route_kmalloc_limit)
136                     kmalloc_raise_limit(M_RTABLE, route_kmalloc_limit);
137 
138           for (cpu = 0; cpu < netisr_ncpus; ++cpu)
139                     bzero(&rtstatistics_percpu[cpu], sizeof(struct rtstatistics));
140           rn_init();      /* initialize all zeroes, all ones, mask table */
141           rtable_init();      /* call dom_rtattach() on each cpu */
142 }
143 
144 static void
rtable_init_oncpu(netmsg_t msg)145 rtable_init_oncpu(netmsg_t msg)
146 {
147           struct domain *dom;
148           int cpu = mycpuid;
149 
150           ASSERT_NETISR_NCPUS(cpu);
151 
152           SLIST_FOREACH(dom, &domains, dom_next) {
153                     if (dom->dom_rtattach) {
154                               dom->dom_rtattach(
155                                         (void **)&rt_tables[cpu][dom->dom_family],
156                                         dom->dom_rtoffset);
157                     }
158           }
159           netisr_forwardmsg(&msg->base, cpu + 1);
160 }
161 
162 static void
rtable_init(void)163 rtable_init(void)
164 {
165           struct netmsg_base msg;
166 
167           netmsg_init(&msg, NULL, &curthread->td_msgport, 0, rtable_init_oncpu);
168           netisr_domsg_global(&msg);
169 }
170 
171 /*
172  * Routing statistics.
173  */
174 static int
sysctl_rtstatistics(SYSCTL_HANDLER_ARGS)175 sysctl_rtstatistics(SYSCTL_HANDLER_ARGS)
176 {
177           int cpu, error = 0;
178 
179           for (cpu = 0; cpu < netisr_ncpus; ++cpu) {
180                     if ((error = SYSCTL_OUT(req, &rtstatistics_percpu[cpu],
181                                                   sizeof(struct rtstatistics))))
182                                         break;
183                     if ((error = SYSCTL_IN(req, &rtstatistics_percpu[cpu],
184                                                   sizeof(struct rtstatistics))))
185                                         break;
186           }
187 
188           return (error);
189 }
190 SYSCTL_PROC(_net_route, OID_AUTO, stats, (CTLTYPE_OPAQUE|CTLFLAG_RW),
191           0, 0, sysctl_rtstatistics, "S,rtstatistics", "Routing statistics");
192 
193 /*
194  * Packet routing routines.
195  */
196 
197 /*
198  * Look up and fill in the "ro_rt" rtentry field in a route structure given
199  * an address in the "ro_dst" field.  Always send a report on a miss and
200  * always clone routes.
201  */
202 void
rtalloc(struct route * ro)203 rtalloc(struct route *ro)
204 {
205           rtalloc_ign(ro, 0UL);
206 }
207 
208 /*
209  * Look up and fill in the "ro_rt" rtentry field in a route structure given
210  * an address in the "ro_dst" field.  Always send a report on a miss and
211  * optionally clone routes when RTF_CLONING or RTF_PRCLONING are not being
212  * ignored.
213  */
214 void
rtalloc_ign(struct route * ro,u_long ignoreflags)215 rtalloc_ign(struct route *ro, u_long ignoreflags)
216 {
217           if (ro->ro_rt != NULL) {
218                     if (ro->ro_rt->rt_ifp != NULL && ro->ro_rt->rt_flags & RTF_UP)
219                               return;
220                     rtfree(ro->ro_rt);
221                     ro->ro_rt = NULL;
222           }
223           ro->ro_rt = _rtlookup(&ro->ro_dst, ignoreflags);
224 }
225 
226 /*
227  * Look up the route that matches the given "dst" address.
228  *
229  * Route lookup can have the side-effect of creating and returning
230  * a cloned route instead when "dst" matches a cloning route and the
231  * RTF_CLONING and RTF_PRCLONING flags are not being ignored.
232  *
233  * Any route returned has its reference count incremented.
234  */
235 struct rtentry *
_rtlookup(struct sockaddr * dst,u_long ignore)236 _rtlookup(struct sockaddr *dst, u_long ignore)
237 {
238           struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
239           struct rtentry *rt;
240 
241           ASSERT_NETISR_NCPUS(mycpuid);
242 
243           if (rnh == NULL)
244                     goto unreach;
245 
246           /*
247            * Look up route in the radix tree.
248            */
249           rt = (struct rtentry *) rnh->rnh_matchaddr(dst, rnh);
250           if (rt == NULL)
251                     goto unreach;
252 
253           /*
254            * Handle cloning routes.
255            */
256           if ((rt->rt_flags & ~ignore & (RTF_CLONING | RTF_PRCLONING)) != 0) {
257                     struct rtentry *clonedroute;
258                     int error;
259 
260                     clonedroute = rt;   /* copy in/copy out parameter */
261                     error = rtrequest(RTM_RESOLVE, dst, NULL, NULL, 0,
262                                           &clonedroute);    /* clone the route */
263                     if (error != 0) {   /* cloning failed */
264                               rt_dstmsg(RTM_MISS, dst, error);
265                               rt->rt_refcnt++;
266                               return (rt);        /* return the uncloned route */
267                     }
268                     if (clonedroute->rt_flags & RTF_XRESOLVE)
269                               rt_dstmsg(RTM_RESOLVE, dst, 0);
270                     return (clonedroute);         /* return cloned route */
271           }
272 
273           /*
274            * Increment the reference count of the matched route and return.
275            */
276           rt->rt_refcnt++;
277           return (rt);
278 
279 unreach:
280           rtstat.rts_unreach++;
281           rt_dstmsg(RTM_MISS, dst, 0);
282           return (NULL);
283 }
284 
285 void
rtfree(struct rtentry * rt)286 rtfree(struct rtentry *rt)
287 {
288 
289           ASSERT_NETISR_NCPUS(rt->rt_cpuid);
290           KASSERT(rt->rt_refcnt > 0, ("rtfree: rt_refcnt %ld", rt->rt_refcnt));
291 
292           --rt->rt_refcnt;
293           if (rt->rt_refcnt == 0) {
294                     struct radix_node_head *rnh =
295                         rt_tables[mycpuid][rt_key(rt)->sa_family];
296 
297                     if (rnh->rnh_close)
298                               rnh->rnh_close((struct radix_node *)rt, rnh);
299                     if (!(rt->rt_flags & RTF_UP)) {
300                               /* deallocate route */
301                               if (rt->rt_ifa != NULL)
302                                         IFAFREE(rt->rt_ifa);
303                               if (rt->rt_parent != NULL)
304                                         RTFREE(rt->rt_parent);        /* recursive call! */
305                               R_Free(rt_key(rt));
306                               R_Free(rt);
307                     }
308           }
309 }
310 
311 static void
rtfree_async_dispatch(netmsg_t msg)312 rtfree_async_dispatch(netmsg_t msg)
313 {
314           struct rtentry *rt = msg->lmsg.u.ms_resultp;
315 
316           rtfree(rt);
317           netisr_replymsg(&msg->base, 0);
318 }
319 
320 void
rtfree_async(struct rtentry * rt)321 rtfree_async(struct rtentry *rt)
322 {
323           struct netmsg_base *msg;
324 
325           if (IN_NETISR_NCPUS(rt->rt_cpuid)) {
326                     rtfree(rt);
327                     return;
328           }
329 
330           KASSERT(rt->rt_refcnt > 0,
331               ("rtfree_async: rt_refcnt %ld", rt->rt_refcnt));
332 
333           msg = kmalloc(sizeof(*msg), M_LWKTMSG, M_INTWAIT);
334           netmsg_init(msg, NULL, &netisr_afree_rport, 0, rtfree_async_dispatch);
335           msg->lmsg.u.ms_resultp = rt;
336 
337           netisr_sendmsg(msg, rt->rt_cpuid);
338 }
339 
340 int
rtredirect_oncpu(struct sockaddr * dst,struct sockaddr * gateway,struct sockaddr * netmask,int flags,struct sockaddr * src)341 rtredirect_oncpu(struct sockaddr *dst, struct sockaddr *gateway,
342                      struct sockaddr *netmask, int flags, struct sockaddr *src)
343 {
344           struct rtentry *rt = NULL;
345           struct rt_addrinfo rtinfo;
346           struct ifaddr *ifa;
347           u_long *stat = NULL;
348           int error;
349 
350           ASSERT_NETISR_NCPUS(mycpuid);
351 
352           /* verify the gateway is directly reachable */
353           if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
354                     error = ENETUNREACH;
355                     goto out;
356           }
357 
358           /*
359            * If the redirect isn't from our current router for this destination,
360            * it's either old or wrong.
361            */
362           if (!(flags & RTF_DONE) &&              /* XXX JH */
363               (rt = rtpurelookup(dst)) != NULL &&
364               (!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) {
365                     error = EINVAL;
366                     goto done;
367           }
368 
369           /*
370            * If it redirects us to ourselves, we have a routing loop,
371            * perhaps as a result of an interface going down recently.
372            */
373           if (ifa_ifwithaddr(gateway)) {
374                     error = EHOSTUNREACH;
375                     goto done;
376           }
377 
378           /*
379            * Create a new entry if the lookup failed or if we got back
380            * a wildcard entry for the default route.  This is necessary
381            * for hosts which use routing redirects generated by smart
382            * gateways to dynamically build the routing tables.
383            */
384           if (rt == NULL)
385                     goto create;
386           if ((rt_mask(rt) != NULL && rt_mask(rt)->sa_len < 2)) {
387                     rtfree(rt);
388                     goto create;
389           }
390 
391           /* Ignore redirects for directly connected hosts. */
392           if (!(rt->rt_flags & RTF_GATEWAY)) {
393                     error = EHOSTUNREACH;
394                     goto done;
395           }
396 
397           if (!(rt->rt_flags & RTF_HOST) && (flags & RTF_HOST)) {
398                     /*
399                      * Changing from a network route to a host route.
400                      * Create a new host route rather than smashing the
401                      * network route.
402                      */
403 create:
404                     flags |=  RTF_GATEWAY | RTF_DYNAMIC;
405                     bzero(&rtinfo, sizeof(struct rt_addrinfo));
406                     rtinfo.rti_info[RTAX_DST] = dst;
407                     rtinfo.rti_info[RTAX_GATEWAY] = gateway;
408                     rtinfo.rti_info[RTAX_NETMASK] = netmask;
409                     rtinfo.rti_flags = flags;
410                     rtinfo.rti_ifa = ifa;
411                     rt = NULL;          /* copy-in/copy-out parameter */
412                     error = rtrequest1(RTM_ADD, &rtinfo, &rt);
413                     if (rt != NULL)
414                               flags = rt->rt_flags;
415                     stat = &rtstat.rts_dynamic;
416           } else {
417                     /*
418                      * Smash the current notion of the gateway to this destination.
419                      * Should check about netmask!!!
420                      */
421                     rt->rt_flags |= RTF_MODIFIED;
422                     flags |= RTF_MODIFIED;
423 
424                     /* We only need to report rtmsg on CPU0 */
425                     rt_setgate(rt, rt_key(rt), gateway);
426                     if (mycpuid == 0)
427                               rt_rtmsg(RTM_CHANGE, rt, rt->rt_ifp, 0);
428                     error = 0;
429                     stat = &rtstat.rts_newgateway;
430           }
431 
432 done:
433           if (rt != NULL)
434                     rtfree(rt);
435 out:
436           if (error != 0)
437                     rtstat.rts_badredirect++;
438           else if (stat != NULL)
439                     (*stat)++;
440 
441           return error;
442 }
443 
444 struct netmsg_rtredirect {
445           struct netmsg_base base;
446           struct sockaddr *dst;
447           struct sockaddr *gateway;
448           struct sockaddr *netmask;
449           int                 flags;
450           struct sockaddr *src;
451 };
452 
453 /*
454  * Force a routing table entry to the specified
455  * destination to go through the given gateway.
456  * Normally called as a result of a routing redirect
457  * message from the network layer.
458  */
459 void
rtredirect(struct sockaddr * dst,struct sockaddr * gateway,struct sockaddr * netmask,int flags,struct sockaddr * src)460 rtredirect(struct sockaddr *dst, struct sockaddr *gateway,
461              struct sockaddr *netmask, int flags, struct sockaddr *src)
462 {
463           struct rt_addrinfo rtinfo;
464           int error;
465           struct netmsg_rtredirect msg;
466 
467           netmsg_init(&msg.base, NULL, &curthread->td_msgport,
468                         0, rtredirect_msghandler);
469           msg.dst = dst;
470           msg.gateway = gateway;
471           msg.netmask = netmask;
472           msg.flags = flags;
473           msg.src = src;
474           error = netisr_domsg_global(&msg.base);
475 
476           bzero(&rtinfo, sizeof(struct rt_addrinfo));
477           rtinfo.rti_info[RTAX_DST] = dst;
478           rtinfo.rti_info[RTAX_GATEWAY] = gateway;
479           rtinfo.rti_info[RTAX_NETMASK] = netmask;
480           rtinfo.rti_info[RTAX_AUTHOR] = src;
481           rt_missmsg(RTM_REDIRECT, &rtinfo, flags, error);
482 }
483 
484 static void
rtredirect_msghandler(netmsg_t msg)485 rtredirect_msghandler(netmsg_t msg)
486 {
487           struct netmsg_rtredirect *rmsg = (void *)msg;
488 
489           rtredirect_oncpu(rmsg->dst, rmsg->gateway, rmsg->netmask,
490                                rmsg->flags, rmsg->src);
491           netisr_forwardmsg(&msg->base, mycpuid + 1);
492 }
493 
494 /*
495  * Routing table ioctl interface.
496  */
497 int
rtioctl(u_long req,caddr_t data,struct ucred * cred)498 rtioctl(u_long req, caddr_t data, struct ucred *cred)
499 {
500 #ifdef INET
501           /* Multicast goop, grrr... */
502           return mrt_ioctl ? mrt_ioctl(req, data) : EOPNOTSUPP;
503 #else
504           return ENXIO;
505 #endif
506 }
507 
508 struct ifaddr *
ifa_ifwithroute(int flags,struct sockaddr * dst,struct sockaddr * gateway)509 ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway)
510 {
511           struct ifaddr *ifa;
512 
513           if (!(flags & RTF_GATEWAY)) {
514                     /*
515                      * If we are adding a route to an interface,
516                      * and the interface is a point-to-point link,
517                      * we should search for the destination
518                      * as our clue to the interface.  Otherwise
519                      * we can use the local address.
520                      */
521                     ifa = NULL;
522                     if (flags & RTF_HOST) {
523                               ifa = ifa_ifwithdstaddr(dst);
524                     }
525                     if (ifa == NULL)
526                               ifa = ifa_ifwithaddr(gateway);
527           } else {
528                     /*
529                      * If we are adding a route to a remote net
530                      * or host, the gateway may still be on the
531                      * other end of a point-to-point link.
532                      */
533                     ifa = ifa_ifwithdstaddr(gateway);
534           }
535           if (ifa == NULL)
536                     ifa = ifa_ifwithnet(gateway);
537           if (ifa == NULL) {
538                     struct rtentry *rt;
539 
540                     rt = rtpurelookup(gateway);
541                     if (rt == NULL)
542                               return (NULL);
543                     rt->rt_refcnt--;
544                     if ((ifa = rt->rt_ifa) == NULL)
545                               return (NULL);
546           }
547           if (ifa->ifa_addr->sa_family != dst->sa_family) {
548                     struct ifaddr *oldifa = ifa;
549 
550                     ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
551                     if (ifa == NULL)
552                               ifa = oldifa;
553           }
554           return (ifa);
555 }
556 
557 static int rt_fixdelete (struct radix_node *, void *);
558 static int rt_fixchange (struct radix_node *, void *);
559 
560 struct rtfc_arg {
561           struct rtentry *rt0;
562           struct radix_node_head *rnh;
563 };
564 
565 /*
566  * Set rtinfo->rti_ifa and rtinfo->rti_ifp.
567  *
568  * Assume that the caller did basic checks to ensure:
569  * - RTAX_DST exists
570  * - RTAX_GATEWAY exists if RTF_GATEWAY is set
571  */
572 int
rt_getifa(struct rt_addrinfo * rtinfo)573 rt_getifa(struct rt_addrinfo *rtinfo)
574 {
575           struct sockaddr *gateway = rtinfo->rti_info[RTAX_GATEWAY];
576           struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
577           struct sockaddr *ifaaddr = rtinfo->rti_info[RTAX_IFA];
578           int flags = rtinfo->rti_flags;
579 
580           /*
581            * ifp may be specified by sockaddr_dl
582            * when protocol address is ambiguous.
583            */
584           if (rtinfo->rti_ifp == NULL) {
585                     struct sockaddr *ifpaddr;
586 
587                     /*
588                      * If we have interface specified by RTAX_IFP address,
589                      * try to use it.
590                      */
591                     ifpaddr = rtinfo->rti_info[RTAX_IFP];
592                     if (ifpaddr != NULL && ifpaddr->sa_family == AF_LINK) {
593                               struct ifaddr *ifa;
594 
595                               ifa = ifa_ifwithnet(ifpaddr);
596                               if (ifa != NULL)
597                                         rtinfo->rti_ifp = ifa->ifa_ifp;
598                     }
599           }
600 
601           /*
602            * If we have source address specified, try to find it.
603            */
604           if (rtinfo->rti_ifa == NULL && ifaaddr != NULL)
605                     rtinfo->rti_ifa = ifa_ifwithaddr(ifaaddr);
606           if (rtinfo->rti_ifa == NULL) {
607                     struct sockaddr *sa;
608 
609                     /*
610                      * Most common use case for the userland-supplied routes.
611                      *
612                      * The IFA is determined by:
613                      * + If ifp is set, try the followings in order:
614                      *   1. IFA address
615                      *   2. Gateway address
616                      *      Note: For interface routes link-level gateway address
617                      *            is specified to indicate the interface index
618                      *            without specifying RTF_GATEWAY.  Ignore the
619                      *            gateway in this case.
620                      *      Note: The gateway may have different AF as the dst.
621                      *            Also ignore the gateway in this case.
622                      *   3. Final destination
623                      *   4. Try to get at least link-level IFA.
624                      *      Note: This allows to add directly-reachable interface
625                      *            prefix to an interface without any IP address.
626                      * + Else:
627                      *   Try to lookup gateway or dst in the routing table to get
628                      *   the IFA.
629                      */
630                     if (ifaaddr != NULL)
631                               sa = ifaaddr;
632                     else if ((flags & RTF_GATEWAY) != 0 &&
633                                gateway->sa_family == dst->sa_family)
634                               sa = gateway;
635                     else
636                               sa = dst;
637                     KKASSERT(sa != NULL);
638 
639                     if (rtinfo->rti_ifp != NULL) {
640                               rtinfo->rti_ifa = ifaof_ifpforaddr(sa, rtinfo->rti_ifp);
641                               if (rtinfo->rti_ifa == NULL &&
642                                   gateway != NULL && gateway != sa)
643                                         rtinfo->rti_ifa =
644                                             ifaof_ifpforaddr(gateway, rtinfo->rti_ifp);
645                     } else if (dst != NULL && gateway != NULL) {
646                               rtinfo->rti_ifa = ifa_ifwithroute(flags, dst, gateway);
647                     } else {
648                               rtinfo->rti_ifa = ifa_ifwithroute(flags, sa, sa);
649                     }
650           }
651           if (rtinfo->rti_ifa == NULL)
652                     return (ENETUNREACH);
653 
654           if (rtinfo->rti_ifp == NULL)
655                     rtinfo->rti_ifp = rtinfo->rti_ifa->ifa_ifp;
656           return (0);
657 }
658 
659 /*
660  * Do appropriate manipulations of a routing tree given
661  * all the bits of info needed
662  */
663 int
rtrequest(int req,struct sockaddr * dst,struct sockaddr * gateway,struct sockaddr * netmask,int flags,struct rtentry ** ret_nrt)664 rtrequest(
665           int req,
666           struct sockaddr *dst,
667           struct sockaddr *gateway,
668           struct sockaddr *netmask,
669           int flags,
670           struct rtentry **ret_nrt)
671 {
672           struct rt_addrinfo rtinfo;
673 
674           bzero(&rtinfo, sizeof(struct rt_addrinfo));
675           rtinfo.rti_info[RTAX_DST] = dst;
676           rtinfo.rti_info[RTAX_GATEWAY] = gateway;
677           rtinfo.rti_info[RTAX_NETMASK] = netmask;
678           rtinfo.rti_flags = flags;
679           return rtrequest1(req, &rtinfo, ret_nrt);
680 }
681 
682 int
rtrequest_global(int req,struct sockaddr * dst,struct sockaddr * gateway,struct sockaddr * netmask,int flags)683 rtrequest_global(
684           int req,
685           struct sockaddr *dst,
686           struct sockaddr *gateway,
687           struct sockaddr *netmask,
688           int flags)
689 {
690           struct rt_addrinfo rtinfo;
691 
692           bzero(&rtinfo, sizeof(struct rt_addrinfo));
693           rtinfo.rti_info[RTAX_DST] = dst;
694           rtinfo.rti_info[RTAX_GATEWAY] = gateway;
695           rtinfo.rti_info[RTAX_NETMASK] = netmask;
696           rtinfo.rti_flags = flags;
697           return rtrequest1_global(req, &rtinfo, NULL, NULL, RTREQ_PRIO_NORM);
698 }
699 
700 struct netmsg_rtq {
701           struct netmsg_base  base;
702           int                           req;
703           struct rt_addrinfo  *rtinfo;
704           rtrequest1_callback_func_t callback;
705           void                          *arg;
706 };
707 
708 int
rtrequest1_global(int req,struct rt_addrinfo * rtinfo,rtrequest1_callback_func_t callback,void * arg,boolean_t req_prio)709 rtrequest1_global(int req, struct rt_addrinfo *rtinfo,
710     rtrequest1_callback_func_t callback, void *arg, boolean_t req_prio)
711 {
712           struct netmsg_rtq msg;
713           int flags = 0;
714 
715           if (req_prio)
716                     flags = MSGF_PRIORITY;
717           netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
718               rtrequest1_msghandler);
719           msg.base.lmsg.ms_error = -1;
720           msg.req = req;
721           msg.rtinfo = rtinfo;
722           msg.callback = callback;
723           msg.arg = arg;
724           return (netisr_domsg_global(&msg.base));
725 }
726 
727 /*
728  * Handle a route table request on the current cpu.  Since the route table's
729  * are supposed to be identical on each cpu, an error occuring later in the
730  * message chain is considered system-fatal.
731  */
732 static void
rtrequest1_msghandler(netmsg_t msg)733 rtrequest1_msghandler(netmsg_t msg)
734 {
735           struct netmsg_rtq *rmsg = (void *)msg;
736           struct rt_addrinfo rtinfo;
737           struct rtentry *rt = NULL;
738           int error;
739 
740           /*
741            * Copy the rtinfo.  We need to make sure that the original
742            * rtinfo, which is setup by the caller, in the netmsg will
743            * _not_ be changed; else the next CPU on the netmsg forwarding
744            * path will see a different rtinfo than what this CPU has seen.
745            */
746           rtinfo = *rmsg->rtinfo;
747 
748           error = rtrequest1(rmsg->req, &rtinfo, &rt);
749           if (rt)
750                     --rt->rt_refcnt;
751           if (rmsg->callback)
752                     rmsg->callback(rmsg->req, error, &rtinfo, rt, rmsg->arg);
753 
754           /*
755            * RTM_DELETE's are propogated even if an error occurs, since a
756            * cloned route might be undergoing deletion and cloned routes
757            * are not necessarily replicated.  An overall error is returned
758            * only if no cpus have the route in question.
759            */
760           if (rmsg->base.lmsg.ms_error < 0 || error == 0)
761                     rmsg->base.lmsg.ms_error = error;
762 
763           if (error && rmsg->req != RTM_DELETE) {
764                     if (mycpuid != 0) {
765                               panic("rtrequest1_msghandler: rtrequest table req %d, "
766                                   "failed on cpu%d, error %d\n",
767                                   rmsg->req, mycpuid, error);
768                     }
769                     netisr_replymsg(&rmsg->base, error);
770           } else {
771                     netisr_forwardmsg_error(&rmsg->base, mycpuid + 1,
772                         rmsg->base.lmsg.ms_error);
773           }
774 }
775 
776 int
rtrequest1(int req,struct rt_addrinfo * rtinfo,struct rtentry ** ret_nrt)777 rtrequest1(int req, struct rt_addrinfo *rtinfo, struct rtentry **ret_nrt)
778 {
779           struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
780           struct rtentry *rt;
781           struct radix_node *rn;
782           struct radix_node_head *rnh;
783           struct ifaddr *ifa;
784           struct sockaddr *ndst;
785           int error = 0;
786 
787           ASSERT_NETISR_NCPUS(mycpuid);
788 
789 #define gotoerr(x) { error = x ; goto bad; }
790 
791 #ifdef ROUTE_DEBUG
792           if (route_debug)
793                     rt_addrinfo_print(req, rtinfo);
794 #endif
795 
796           crit_enter();
797           /*
798            * Find the correct routing tree to use for this Address Family
799            */
800           if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL)
801                     gotoerr(EAFNOSUPPORT);
802 
803           /*
804            * If we are adding a host route then we don't want to put
805            * a netmask in the tree, nor do we want to clone it.
806            */
807           if (rtinfo->rti_flags & RTF_HOST) {
808                     rtinfo->rti_info[RTAX_NETMASK] = NULL;
809                     rtinfo->rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
810           }
811 
812           switch (req) {
813           case RTM_DELETE:
814                     /* Remove the item from the tree. */
815                     rn = rnh->rnh_deladdr(rtinfo->rti_info[RTAX_DST],
816                                               rtinfo->rti_info[RTAX_NETMASK], rnh);
817                     if (rn == NULL)
818                               gotoerr(ESRCH);
819                     KASSERT(!(rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)),
820                               ("rnh_deladdr returned flags 0x%x", rn->rn_flags));
821                     rt = (struct rtentry *)rn;
822 
823                     /* ref to prevent a deletion race */
824                     ++rt->rt_refcnt;
825 
826                     /* Free any routes cloned from this one. */
827                     if ((rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) &&
828                         rt_mask(rt) != NULL) {
829                               rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
830                                                          rt_fixdelete, rt);
831                     }
832 
833                     if (rt->rt_gwroute != NULL) {
834                               RTFREE(rt->rt_gwroute);
835                               rt->rt_gwroute = NULL;
836                     }
837 
838                     /*
839                      * NB: RTF_UP must be set during the search above,
840                      * because we might delete the last ref, causing
841                      * rt to get freed prematurely.
842                      */
843                     rt->rt_flags &= ~RTF_UP;
844 
845 #ifdef ROUTE_DEBUG
846                     if (route_debug)
847                               rt_print(rtinfo, rt);
848 #endif
849 
850                     /* Give the protocol a chance to keep things in sync. */
851                     if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
852                               ifa->ifa_rtrequest(RTM_DELETE, rt);
853 
854                     /*
855                      * If the caller wants it, then it can have it,
856                      * but it's up to it to free the rtentry as we won't be
857                      * doing it.
858                      */
859                     KASSERT(rt->rt_refcnt >= 0,
860                               ("rtrequest1(DELETE): refcnt %ld", rt->rt_refcnt));
861                     if (ret_nrt != NULL) {
862                               /* leave ref intact for return */
863                               *ret_nrt = rt;
864                     } else {
865                               /* deref / attempt to destroy */
866                               rtfree(rt);
867                     }
868                     break;
869 
870           case RTM_RESOLVE:
871                     if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
872                               gotoerr(EINVAL);
873 
874                     if (!(rt->rt_ifp->if_flags & IFF_UP))
875                               gotoerr(ENETDOWN);
876 
877                     KASSERT(rt->rt_cpuid == mycpuid,
878                               ("rt resolve rt_cpuid %d, mycpuid %d",
879                                rt->rt_cpuid, mycpuid));
880 
881                     ifa = rt->rt_ifa;
882                     rtinfo->rti_flags =
883                         rt->rt_flags & ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
884                     rtinfo->rti_flags |= RTF_WASCLONED;
885                     rtinfo->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
886                     if ((rtinfo->rti_info[RTAX_NETMASK] = rt->rt_genmask) == NULL)
887                               rtinfo->rti_flags |= RTF_HOST;
888                     rtinfo->rti_info[RTAX_MPLS1] = rt->rt_shim[0];
889                     rtinfo->rti_info[RTAX_MPLS2] = rt->rt_shim[1];
890                     rtinfo->rti_info[RTAX_MPLS3] = rt->rt_shim[2];
891                     goto makeroute;
892 
893           case RTM_ADD:
894                     KASSERT((!(rtinfo->rti_flags & RTF_GATEWAY) ||
895                                rtinfo->rti_info[RTAX_GATEWAY] != NULL),
896                               ("rtrequest: GATEWAY but no gateway"));
897 
898                     if (rtinfo->rti_ifa == NULL &&
899                         (error = rt_getifa(rtinfo)) != 0)
900                               gotoerr(error);
901                     ifa = rtinfo->rti_ifa;
902 makeroute:
903                     R_Malloc(rt, struct rtentry *, sizeof(struct rtentry));
904                     if (rt == NULL) {
905                               if (req == RTM_ADD)
906                                         kprintf("%s: alloc rtentry failed on cpu%d\n",
907                                                   __func__, mycpuid);
908                               gotoerr(ENOBUFS);
909                     }
910                     bzero(rt, sizeof(struct rtentry));
911                     rt->rt_flags = RTF_UP | rtinfo->rti_flags;
912                     rt->rt_cpuid = mycpuid;
913 
914                     error = rt_setgate(rt, dst, rtinfo->rti_info[RTAX_GATEWAY]);
915                     if (error != 0) {
916                               R_Free(rt);
917                               gotoerr(error);
918                     }
919 
920                     ndst = rt_key(rt);
921                     if (rtinfo->rti_info[RTAX_NETMASK] != NULL)
922                               rt_maskedcopy(dst, ndst,
923                                               rtinfo->rti_info[RTAX_NETMASK]);
924                     else
925                               bcopy(dst, ndst, dst->sa_len);
926 
927                     if (rtinfo->rti_info[RTAX_MPLS1] != NULL)
928                               rt_setshims(rt, rtinfo->rti_info);
929 
930                     /*
931                      * Note that we now have a reference to the ifa.
932                      * This moved from below so that rnh->rnh_addaddr() can
933                      * examine the ifa and ifa->ifa_ifp if it so desires.
934                      */
935                     IFAREF(ifa);
936                     rt->rt_ifa = ifa;
937                     rt->rt_ifp = ifa->ifa_ifp;
938                     /* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
939 
940                     rn = rnh->rnh_addaddr(ndst, rtinfo->rti_info[RTAX_NETMASK],
941                                               rnh, rt->rt_nodes);
942                     if (rn == NULL) {
943                               struct rtentry *oldrt;
944 
945                               /*
946                                * We already have one of these in the tree.
947                                * We do a special hack: if the old route was
948                                * cloned, then we blow it away and try
949                                * re-inserting the new one.
950                                */
951                               oldrt = rtpurelookup(ndst);
952                               if (oldrt != NULL) {
953                                         --oldrt->rt_refcnt;
954                                         if (oldrt->rt_flags & RTF_WASCLONED) {
955                                                   rtrequest(RTM_DELETE, rt_key(oldrt),
956                                                               oldrt->rt_gateway,
957                                                               rt_mask(oldrt),
958                                                               oldrt->rt_flags, NULL);
959                                                   rn = rnh->rnh_addaddr(ndst,
960                                                       rtinfo->rti_info[RTAX_NETMASK],
961                                                       rnh, rt->rt_nodes);
962                                         }
963                               }
964                     }
965                     /* NOTE: rt_ifa may have been changed */
966                     ifa = rt->rt_ifa;
967 
968                     /*
969                      * If it still failed to go into the tree,
970                      * then un-make it (this should be a function).
971                      */
972                     if (rn == NULL) {
973                               if (rt->rt_gwroute != NULL)
974                                         rtfree(rt->rt_gwroute);
975                               IFAFREE(ifa);
976                               R_Free(rt_key(rt));
977                               R_Free(rt);
978                               gotoerr(EEXIST);
979                     }
980 
981                     /*
982                      * If we got here from RESOLVE, then we are cloning
983                      * so clone the rest, and note that we
984                      * are a clone (and increment the parent's references)
985                      */
986                     if (req == RTM_RESOLVE) {
987                               rt->rt_rmx = (*ret_nrt)->rt_rmx;    /* copy metrics */
988                               rt->rt_rmx.rmx_pksent = 0;  /* reset packet counter */
989                               if ((*ret_nrt)->rt_flags &
990                                                (RTF_CLONING | RTF_PRCLONING)) {
991                                         rt->rt_parent = *ret_nrt;
992                                         (*ret_nrt)->rt_refcnt++;
993                               }
994                     }
995 
996                     /*
997                      * if this protocol has something to add to this then
998                      * allow it to do that as well.
999                      */
1000                     if (ifa->ifa_rtrequest != NULL)
1001                               ifa->ifa_rtrequest(req, rt);
1002 
1003                     /*
1004                      * We repeat the same procedure from rt_setgate() here because
1005                      * it doesn't fire when we call it there because the node
1006                      * hasn't been added to the tree yet.
1007                      */
1008                     if (req == RTM_ADD && !(rt->rt_flags & RTF_HOST) &&
1009                         rt_mask(rt) != NULL) {
1010                               struct rtfc_arg arg = { rt, rnh };
1011 
1012                               rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
1013                                                          rt_fixchange, &arg);
1014                     }
1015 
1016 #ifdef ROUTE_DEBUG
1017                     if (route_debug)
1018                               rt_print(rtinfo, rt);
1019 #endif
1020                     /*
1021                      * Return the resulting rtentry,
1022                      * increasing the number of references by one.
1023                      */
1024                     if (ret_nrt != NULL) {
1025                               rt->rt_refcnt++;
1026                               *ret_nrt = rt;
1027                     }
1028                     break;
1029           case RTM_GET:
1030                     /* Get the item from the tree. */
1031                     rn = rnh->rnh_lookup(rtinfo->rti_info[RTAX_DST],
1032                                              rtinfo->rti_info[RTAX_NETMASK], rnh);
1033                     if (rn == NULL)
1034                               gotoerr(ESRCH);
1035                     if (ret_nrt != NULL) {
1036                               rt = (struct rtentry *)rn;
1037                               rt->rt_refcnt++;
1038                               *ret_nrt = rt;
1039                     }
1040                     break;
1041           default:
1042                     error = EOPNOTSUPP;
1043           }
1044 bad:
1045 #ifdef ROUTE_DEBUG
1046           if (route_debug) {
1047                     if (error)
1048                               kprintf("rti %p failed error %d\n", rtinfo, error);
1049                     else
1050                               kprintf("rti %p succeeded\n", rtinfo);
1051           }
1052 #endif
1053           crit_exit();
1054           return (error);
1055 }
1056 
1057 /*
1058  * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
1059  * (i.e., the routes related to it by the operation of cloning).  This
1060  * routine is iterated over all potential former-child-routes by way of
1061  * rnh->rnh_walktree_from() above, and those that actually are children of
1062  * the late parent (passed in as VP here) are themselves deleted.
1063  */
1064 static int
rt_fixdelete(struct radix_node * rn,void * vp)1065 rt_fixdelete(struct radix_node *rn, void *vp)
1066 {
1067           struct rtentry *rt = (struct rtentry *)rn;
1068           struct rtentry *rt0 = vp;
1069 
1070           if (rt->rt_parent == rt0 &&
1071               !(rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1072                     return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1073                                          rt->rt_flags, NULL);
1074           }
1075           return 0;
1076 }
1077 
1078 /*
1079  * This routine is called from rt_setgate() to do the analogous thing for
1080  * adds and changes.  There is the added complication in this case of a
1081  * middle insert; i.e., insertion of a new network route between an older
1082  * network route and (cloned) host routes.  For this reason, a simple check
1083  * of rt->rt_parent is insufficient; each candidate route must be tested
1084  * against the (mask, value) of the new route (passed as before in vp)
1085  * to see if the new route matches it.
1086  *
1087  * XXX - it may be possible to do fixdelete() for changes and reserve this
1088  * routine just for adds.  I'm not sure why I thought it was necessary to do
1089  * changes this way.
1090  */
1091 #ifdef DEBUG
1092 static int rtfcdebug = 0;
1093 #endif
1094 
1095 static int
rt_fixchange(struct radix_node * rn,void * vp)1096 rt_fixchange(struct radix_node *rn, void *vp)
1097 {
1098           struct rtentry *rt = (struct rtentry *)rn;
1099           struct rtfc_arg *ap = vp;
1100           struct rtentry *rt0 = ap->rt0;
1101           struct radix_node_head *rnh = ap->rnh;
1102           u_char *xk1, *xm1, *xk2, *xmp;
1103           int i, len, mlen;
1104 
1105 #ifdef DEBUG
1106           if (rtfcdebug)
1107                     kprintf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
1108 #endif
1109 
1110           if (rt->rt_parent == NULL ||
1111               (rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1112 #ifdef DEBUG
1113                     if (rtfcdebug) kprintf("no parent, pinned or cloning\n");
1114 #endif
1115                     return 0;
1116           }
1117 
1118           if (rt->rt_parent == rt0) {
1119 #ifdef DEBUG
1120                     if (rtfcdebug) kprintf("parent match\n");
1121 #endif
1122                     return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1123                                          rt->rt_flags, NULL);
1124           }
1125 
1126           /*
1127            * There probably is a function somewhere which does this...
1128            * if not, there should be.
1129            */
1130           len = imin(rt_key(rt0)->sa_len, rt_key(rt)->sa_len);
1131 
1132           xk1 = (u_char *)rt_key(rt0);
1133           xm1 = (u_char *)rt_mask(rt0);
1134           xk2 = (u_char *)rt_key(rt);
1135 
1136           /* avoid applying a less specific route */
1137           xmp = (u_char *)rt_mask(rt->rt_parent);
1138           mlen = rt_key(rt->rt_parent)->sa_len;
1139           if (mlen > rt_key(rt0)->sa_len) {
1140 #ifdef DEBUG
1141                     if (rtfcdebug)
1142                               kprintf("rt_fixchange: inserting a less "
1143                                      "specific route\n");
1144 #endif
1145                     return 0;
1146           }
1147           for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) {
1148                     if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) {
1149 #ifdef DEBUG
1150                               if (rtfcdebug)
1151                                         kprintf("rt_fixchange: inserting a less "
1152                                                "specific route\n");
1153 #endif
1154                               return 0;
1155                     }
1156           }
1157 
1158           for (i = rnh->rnh_treetop->rn_offset; i < len; i++) {
1159                     if ((xk2[i] & xm1[i]) != xk1[i]) {
1160 #ifdef DEBUG
1161                               if (rtfcdebug) kprintf("no match\n");
1162 #endif
1163                               return 0;
1164                     }
1165           }
1166 
1167           /*
1168            * OK, this node is a clone, and matches the node currently being
1169            * changed/added under the node's mask.  So, get rid of it.
1170            */
1171 #ifdef DEBUG
1172           if (rtfcdebug) kprintf("deleting\n");
1173 #endif
1174           return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1175                                rt->rt_flags, NULL);
1176 }
1177 
1178 int
rt_setgate(struct rtentry * rt0,struct sockaddr * dst,struct sockaddr * gate)1179 rt_setgate(struct rtentry *rt0, struct sockaddr *dst, struct sockaddr *gate)
1180 {
1181           char *space, *oldspace;
1182           int dlen = RT_ROUNDUP(dst->sa_len), glen = RT_ROUNDUP(gate->sa_len);
1183           struct rtentry *rt = rt0;
1184           struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
1185 
1186           ASSERT_NETISR_NCPUS(mycpuid);
1187 
1188           /*
1189            * A host route with the destination equal to the gateway
1190            * will interfere with keeping LLINFO in the routing
1191            * table, so disallow it.
1192            */
1193           if (((rt0->rt_flags & (RTF_HOST | RTF_GATEWAY | RTF_LLINFO)) ==
1194                                     (RTF_HOST | RTF_GATEWAY)) &&
1195               dst->sa_len == gate->sa_len &&
1196               sa_equal(dst, gate)) {
1197                     /*
1198                      * The route might already exist if this is an RTM_CHANGE
1199                      * or a routing redirect, so try to delete it.
1200                      */
1201                     if (rt_key(rt0) != NULL)
1202                               rtrequest(RTM_DELETE, rt_key(rt0), rt0->rt_gateway,
1203                                           rt_mask(rt0), rt0->rt_flags, NULL);
1204                     return EADDRNOTAVAIL;
1205           }
1206 
1207           /*
1208            * Both dst and gateway are stored in the same malloc'ed chunk
1209            * (If I ever get my hands on....)
1210            * if we need to malloc a new chunk, then keep the old one around
1211            * till we don't need it any more.
1212            */
1213           if (rt->rt_gateway == NULL ||
1214               glen > RT_ROUNDUP(rt->rt_gateway->sa_len)) {
1215                     oldspace = (char *)rt_key(rt);
1216                     R_Malloc(space, char *, dlen + glen);
1217                     if (space == NULL)
1218                               return ENOBUFS;
1219                     rt->rt_nodes->rn_key = space;
1220           } else {
1221                     space = (char *)rt_key(rt);   /* Just use the old space. */
1222                     oldspace = NULL;
1223           }
1224 
1225           /* Set the gateway value. */
1226           rt->rt_gateway = (struct sockaddr *)(space + dlen);
1227           bcopy(gate, rt->rt_gateway, glen);
1228 
1229           if (oldspace != NULL) {
1230                     /*
1231                      * If we allocated a new chunk, preserve the original dst.
1232                      * This way, rt_setgate() really just sets the gate
1233                      * and leaves the dst field alone.
1234                      */
1235                     bcopy(dst, space, dlen);
1236                     R_Free(oldspace);
1237           }
1238 
1239           /*
1240            * If there is already a gwroute, it's now almost definitely wrong
1241            * so drop it.
1242            */
1243           if (rt->rt_gwroute != NULL) {
1244                     RTFREE(rt->rt_gwroute);
1245                     rt->rt_gwroute = NULL;
1246           }
1247           if (rt->rt_flags & RTF_GATEWAY) {
1248                     /*
1249                      * Cloning loop avoidance: In the presence of
1250                      * protocol-cloning and bad configuration, it is
1251                      * possible to get stuck in bottomless mutual recursion
1252                      * (rtrequest rt_setgate rtlookup).  We avoid this
1253                      * by not allowing protocol-cloning to operate for
1254                      * gateways (which is probably the correct choice
1255                      * anyway), and avoid the resulting reference loops
1256                      * by disallowing any route to run through itself as
1257                      * a gateway.  This is obviously mandatory when we
1258                      * get rt->rt_output().
1259                      *
1260                      * This breaks TTCP for hosts outside the gateway!  XXX JH
1261                      */
1262                     rt->rt_gwroute = _rtlookup(gate, RTF_PRCLONING);
1263                     if (rt->rt_gwroute == rt) {
1264                               rt->rt_gwroute = NULL;
1265                               --rt->rt_refcnt;
1266                               return EDQUOT; /* failure */
1267                     }
1268           }
1269 
1270           /*
1271            * This isn't going to do anything useful for host routes, so
1272            * don't bother.  Also make sure we have a reasonable mask
1273            * (we don't yet have one during adds).
1274            */
1275           if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != NULL) {
1276                     struct rtfc_arg arg = { rt, rnh };
1277 
1278                     rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
1279                                                rt_fixchange, &arg);
1280           }
1281 
1282           return 0;
1283 }
1284 
1285 static void
rt_maskedcopy(struct sockaddr * src,struct sockaddr * dst,struct sockaddr * netmask)1286 rt_maskedcopy(
1287           struct sockaddr *src,
1288           struct sockaddr *dst,
1289           struct sockaddr *netmask)
1290 {
1291           u_char *cp1 = (u_char *)src;
1292           u_char *cp2 = (u_char *)dst;
1293           u_char *cp3 = (u_char *)netmask;
1294           u_char *cplim = cp2 + *cp3;
1295           u_char *cplim2 = cp2 + *cp1;
1296 
1297           *cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
1298           cp3 += 2;
1299           if (cplim > cplim2)
1300                     cplim = cplim2;
1301           while (cp2 < cplim)
1302                     *cp2++ = *cp1++ & *cp3++;
1303           if (cp2 < cplim2)
1304                     bzero(cp2, cplim2 - cp2);
1305 }
1306 
1307 int
rt_llroute(struct sockaddr * dst,struct rtentry * rt0,struct rtentry ** drt)1308 rt_llroute(struct sockaddr *dst, struct rtentry *rt0, struct rtentry **drt)
1309 {
1310           struct rtentry *up_rt, *rt;
1311 
1312           ASSERT_NETISR_NCPUS(mycpuid);
1313 
1314           if (!(rt0->rt_flags & RTF_UP)) {
1315                     up_rt = rtlookup(dst);
1316                     if (up_rt == NULL)
1317                               return (EHOSTUNREACH);
1318                     up_rt->rt_refcnt--;
1319           } else
1320                     up_rt = rt0;
1321           if (up_rt->rt_flags & RTF_GATEWAY) {
1322                     if (up_rt->rt_gwroute == NULL) {
1323                               up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1324                               if (up_rt->rt_gwroute == NULL)
1325                                         return (EHOSTUNREACH);
1326                     } else if (!(up_rt->rt_gwroute->rt_flags & RTF_UP)) {
1327                               rtfree(up_rt->rt_gwroute);
1328                               up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1329                               if (up_rt->rt_gwroute == NULL)
1330                                         return (EHOSTUNREACH);
1331                     }
1332                     rt = up_rt->rt_gwroute;
1333           } else
1334                     rt = up_rt;
1335           if (rt->rt_flags & RTF_REJECT &&
1336               (rt->rt_rmx.rmx_expire == 0 ||                /* rt doesn't expire */
1337                time_uptime < rt->rt_rmx.rmx_expire))        /* rt not expired */
1338                     return (rt->rt_flags & RTF_HOST ?  EHOSTDOWN : EHOSTUNREACH);
1339           *drt = rt;
1340           return 0;
1341 }
1342 
1343 struct rt_purgecloned_arg {
1344           struct ifnet        *ifp;
1345           int                 family;
1346 };
1347 
1348 static int
rt_purgecloned_callback(struct radix_node * rn,void * xap)1349 rt_purgecloned_callback(struct radix_node *rn, void *xap)
1350 {
1351           struct rtentry *rt = (struct rtentry *)rn;
1352           struct rt_purgecloned_arg *arg = xap;
1353 
1354           if (rt->rt_ifp == arg->ifp && rt->rt_flags & RTF_WASCLONED)
1355                     rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
1356           return 0;
1357 }
1358 
1359 void
rt_purgecloned(struct ifnet * ifp,int af)1360 rt_purgecloned(struct ifnet *ifp, int af)
1361 {
1362           struct radix_node_head *rnh;
1363           struct rt_purgecloned_arg arg = {
1364                     .ifp = ifp,
1365                     .family = af,
1366           };
1367 
1368           ASSERT_NETISR0;
1369 
1370           if ((rnh = rt_tables[mycpuid][af]) != NULL)
1371                     rnh->rnh_walktree(rnh, rt_purgecloned_callback, &arg);
1372 }
1373 
1374 static int
rt_setshims(struct rtentry * rt,struct sockaddr ** rt_shim)1375 rt_setshims(struct rtentry *rt, struct sockaddr **rt_shim){
1376           int i;
1377 
1378           for (i=0; i<3; i++) {
1379                     struct sockaddr *shim = rt_shim[RTAX_MPLS1 + i];
1380                     int shimlen;
1381 
1382                     if (shim == NULL)
1383                               break;
1384 
1385                     shimlen = RT_ROUNDUP(shim->sa_len);
1386                     R_Malloc(rt->rt_shim[i], struct sockaddr *, shimlen);
1387                     bcopy(shim, rt->rt_shim[i], shimlen);
1388           }
1389 
1390           return 0;
1391 }
1392 
1393 #ifdef ROUTE_DEBUG
1394 
1395 /*
1396  * Print out a route table entry
1397  */
1398 void
rt_print(struct rt_addrinfo * rtinfo,struct rtentry * rt)1399 rt_print(struct rt_addrinfo *rtinfo, struct rtentry *rt)
1400 {
1401           kprintf("rti %p cpu %d route %p flags %08lx: ",
1402                     rtinfo, mycpuid, rt, rt->rt_flags);
1403           sockaddr_print(rt_key(rt));
1404           kprintf(" mask ");
1405           sockaddr_print(rt_mask(rt));
1406           kprintf(" gw ");
1407           sockaddr_print(rt->rt_gateway);
1408           kprintf(" ifp \"%s\"", rt->rt_ifp ? rt->rt_ifp->if_xname : "?");
1409           kprintf(" ifa %p\n", rt->rt_ifa);
1410 }
1411 
1412 void
rt_addrinfo_print(int cmd,struct rt_addrinfo * rti)1413 rt_addrinfo_print(int cmd, struct rt_addrinfo *rti)
1414 {
1415           int didit = 0;
1416           int i;
1417 
1418 #ifdef ROUTE_DEBUG
1419           if (cmd == RTM_DELETE && route_debug > 1)
1420                     print_backtrace(-1);
1421 #endif
1422 
1423           switch(cmd) {
1424           case RTM_ADD:
1425                     kprintf("ADD ");
1426                     break;
1427           case RTM_RESOLVE:
1428                     kprintf("RES ");
1429                     break;
1430           case RTM_DELETE:
1431                     kprintf("DEL ");
1432                     break;
1433           default:
1434                     kprintf("C%02d ", cmd);
1435                     break;
1436           }
1437           kprintf("rti %p cpu %d flags %08x ", rti, mycpuid, rti->rti_flags);
1438           for (i = 0; i < RTAX_MAX; ++i) {
1439                     if (rti->rti_info[i] == NULL)
1440                               continue;
1441                     if (didit)
1442                               kprintf(", ");
1443                     switch (i) {
1444                     case RTAX_DST:
1445                               kprintf("(DST ");
1446                               break;
1447                     case RTAX_GATEWAY:
1448                               kprintf("(GWY ");
1449                               break;
1450                     case RTAX_NETMASK:
1451                               kprintf("(MSK ");
1452                               break;
1453                     case RTAX_GENMASK:
1454                               kprintf("(GEN ");
1455                               break;
1456                     case RTAX_IFP:
1457                               kprintf("(IFP ");
1458                               break;
1459                     case RTAX_IFA:
1460                               kprintf("(IFA ");
1461                               break;
1462                     case RTAX_AUTHOR:
1463                               kprintf("(AUT ");
1464                               break;
1465                     case RTAX_BRD:
1466                               kprintf("(BRD ");
1467                               break;
1468                     default:
1469                               kprintf("(?%02d ", i);
1470                               break;
1471                     }
1472                     sockaddr_print(rti->rti_info[i]);
1473                     kprintf(")");
1474                     didit = 1;
1475           }
1476           kprintf(" ifp \"%s\"", rti->rti_ifp ? rti->rti_ifp->if_xname : "?");
1477           kprintf(" ifa %p\n", rti->rti_ifa);
1478 }
1479 
1480 void
sockaddr_print(const struct sockaddr * sa)1481 sockaddr_print(const struct sockaddr *sa)
1482 {
1483           const struct sockaddr_in *sa4;
1484           const struct sockaddr_in6 *sa6;
1485           int len;
1486           int i;
1487 
1488           if (sa == NULL) {
1489                     kprintf("NULL");
1490                     return;
1491           }
1492 
1493           switch (sa->sa_family) {
1494           case AF_INET:
1495                     sa4 = (const struct sockaddr_in *)sa;
1496                     kprintf("INET %d %d.%d.%d.%d",
1497                               ntohs(sa4->sin_port),
1498                               (ntohl(sa4->sin_addr.s_addr) >> 24) & 255,
1499                               (ntohl(sa4->sin_addr.s_addr) >> 16) & 255,
1500                               (ntohl(sa4->sin_addr.s_addr) >> 8) & 255,
1501                               (ntohl(sa4->sin_addr.s_addr) >> 0) & 255
1502                     );
1503                     break;
1504           case AF_INET6:
1505                     sa6 = (const struct sockaddr_in6 *)sa;
1506                     kprintf("INET6 %d %04x:%04x%04x:%04x:%04x:%04x:%04x:%04x",
1507                               ntohs(sa6->sin6_port),
1508                               ntohs(sa6->sin6_addr.s6_addr16[0]),
1509                               ntohs(sa6->sin6_addr.s6_addr16[1]),
1510                               ntohs(sa6->sin6_addr.s6_addr16[2]),
1511                               ntohs(sa6->sin6_addr.s6_addr16[3]),
1512                               ntohs(sa6->sin6_addr.s6_addr16[4]),
1513                               ntohs(sa6->sin6_addr.s6_addr16[5]),
1514                               ntohs(sa6->sin6_addr.s6_addr16[6]),
1515                               ntohs(sa6->sin6_addr.s6_addr16[7])
1516                     );
1517                     break;
1518           default:
1519                     kprintf("AF%d ", sa->sa_family);
1520                     len = sa->sa_len - offsetof(struct sockaddr, sa_data[0]);
1521                     while (len > 0 && sa->sa_data[len-1] == 0)
1522                               --len;
1523                     for (i = 0; i < len; ++i) {
1524                               if (i)
1525                                         kprintf(".");
1526                               kprintf("%d", (unsigned char)sa->sa_data[i]);
1527                     }
1528                     break;
1529           }
1530 }
1531 
1532 #endif
1533 
1534 /*
1535  * Set up a routing table entry, normally for an interface.
1536  */
1537 int
rtinit(struct ifaddr * ifa,int cmd,int flags)1538 rtinit(struct ifaddr *ifa, int cmd, int flags)
1539 {
1540           struct sockaddr *dst, *deldst, *netmask;
1541           struct mbuf *m = NULL;
1542           struct radix_node_head *rnh;
1543           struct radix_node *rn;
1544           struct rt_addrinfo rtinfo;
1545           int error;
1546 
1547           ASSERT_NETISR0;
1548 
1549           if (flags & RTF_HOST) {
1550                     dst = ifa->ifa_dstaddr;
1551                     netmask = NULL;
1552           } else {
1553                     dst = ifa->ifa_addr;
1554                     netmask = ifa->ifa_netmask;
1555           }
1556           /*
1557            * If it's a delete, check that if it exists, it's on the correct
1558            * interface or we might scrub a route to another ifa which would
1559            * be confusing at best and possibly worse.
1560            */
1561           if (cmd == RTM_DELETE) {
1562                     /*
1563                      * It's a delete, so it should already exist..
1564                      * If it's a net, mask off the host bits
1565                      * (Assuming we have a mask)
1566                      */
1567                     if (netmask != NULL) {
1568                               m = m_get(M_NOWAIT, MT_SONAME);
1569                               if (m == NULL)
1570                                         return (ENOBUFS);
1571                               mbuftrackid(m, 34);
1572                               deldst = mtod(m, struct sockaddr *);
1573                               rt_maskedcopy(dst, deldst, netmask);
1574                               dst = deldst;
1575                     }
1576                     /*
1577                      * Look up an rtentry that is in the routing tree and
1578                      * contains the correct info.
1579                      */
1580                     if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL ||
1581                         (rn = rnh->rnh_lookup(dst, netmask, rnh)) == NULL ||
1582                         ((struct rtentry *)rn)->rt_ifa != ifa ||
1583                         !sa_equal((const struct sockaddr *)rn->rn_key, dst)) {
1584                               if (m != NULL)
1585                                         m_free(m);
1586                               return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1587                     }
1588                     /* XXX */
1589 #if 0
1590                     else {
1591                               /*
1592                                * One would think that as we are deleting, and we know
1593                                * it doesn't exist, we could just return at this point
1594                                * with an "ELSE" clause, but apparently not..
1595                                */
1596                               return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1597                     }
1598 #endif
1599           }
1600           /*
1601            * Do the actual request
1602            */
1603           bzero(&rtinfo, sizeof(struct rt_addrinfo));
1604           rtinfo.rti_info[RTAX_DST] = dst;
1605           rtinfo.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
1606           rtinfo.rti_info[RTAX_NETMASK] = netmask;
1607           rtinfo.rti_flags = flags | ifa->ifa_flags;
1608           rtinfo.rti_ifa = ifa;
1609           error = rtrequest1_global(cmd, &rtinfo, rtinit_rtrequest_callback, ifa,
1610               RTREQ_PRIO_HIGH);
1611           if (m != NULL)
1612                     m_free(m);
1613           return (error);
1614 }
1615 
1616 static void
rtinit_rtrequest_callback(int cmd,int error,struct rt_addrinfo * rtinfo,struct rtentry * rt,void * arg)1617 rtinit_rtrequest_callback(int cmd, int error,
1618                                 struct rt_addrinfo *rtinfo, struct rtentry *rt,
1619                                 void *arg)
1620 {
1621           struct ifaddr *ifa = arg;
1622 
1623           if (error == 0 && rt) {
1624                     if (mycpuid == 0)
1625                               rt_newaddrmsg(cmd, ifa, error, rt);
1626                     if (cmd == RTM_DELETE) {
1627                               if (rt->rt_refcnt == 0) {
1628                                         ++rt->rt_refcnt;
1629                                         rtfree(rt);
1630                               }
1631                     }
1632           }
1633 }
1634 
1635 struct netmsg_rts {
1636           struct netmsg_base  base;
1637           int                           req;
1638           struct rt_addrinfo  *rtinfo;
1639           rtsearch_callback_func_t callback;
1640           void                          *arg;
1641           boolean_t           exact_match;
1642           int                           found_cnt;
1643 };
1644 
1645 int
rtsearch_global(int req,struct rt_addrinfo * rtinfo,rtsearch_callback_func_t callback,void * arg,boolean_t exact_match,boolean_t req_prio)1646 rtsearch_global(int req, struct rt_addrinfo *rtinfo,
1647     rtsearch_callback_func_t callback, void *arg, boolean_t exact_match,
1648     boolean_t req_prio)
1649 {
1650           struct netmsg_rts msg;
1651           int flags = 0;
1652 
1653           if (req_prio)
1654                     flags = MSGF_PRIORITY;
1655           netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
1656               rtsearch_msghandler);
1657           msg.req = req;
1658           msg.rtinfo = rtinfo;
1659           msg.callback = callback;
1660           msg.arg = arg;
1661           msg.exact_match = exact_match;
1662           msg.found_cnt = 0;
1663           return (netisr_domsg_global(&msg.base));
1664 }
1665 
1666 static void
rtsearch_msghandler(netmsg_t msg)1667 rtsearch_msghandler(netmsg_t msg)
1668 {
1669           struct netmsg_rts *rmsg = (void *)msg;
1670           struct rt_addrinfo rtinfo;
1671           struct radix_node_head *rnh;
1672           struct rtentry *rt;
1673           int error;
1674 
1675           ASSERT_NETISR_NCPUS(mycpuid);
1676 
1677           /*
1678            * Copy the rtinfo.  We need to make sure that the original
1679            * rtinfo, which is setup by the caller, in the netmsg will
1680            * _not_ be changed; else the next CPU on the netmsg forwarding
1681            * path will see a different rtinfo than what this CPU has seen.
1682            */
1683           rtinfo = *rmsg->rtinfo;
1684 
1685           /*
1686            * Find the correct routing tree to use for this Address Family
1687            */
1688           if ((rnh = rt_tables[mycpuid][rtinfo.rti_dst->sa_family]) == NULL) {
1689                     if (mycpuid != 0)
1690                               panic("partially initialized routing tables");
1691                     netisr_replymsg(&rmsg->base, EAFNOSUPPORT);
1692                     return;
1693           }
1694 
1695           /*
1696            * Correct rtinfo for the host route searching.
1697            */
1698           if (rtinfo.rti_flags & RTF_HOST) {
1699                     rtinfo.rti_netmask = NULL;
1700                     rtinfo.rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
1701           }
1702 
1703           rt = (struct rtentry *)
1704                rnh->rnh_lookup(rtinfo.rti_dst, rtinfo.rti_netmask, rnh);
1705 
1706           /*
1707            * If we are asked to do the "exact match", we need to make sure
1708            * that host route searching got a host route while a network
1709            * route searching got a network route.
1710            */
1711           if (rt != NULL && rmsg->exact_match &&
1712               ((rt->rt_flags ^ rtinfo.rti_flags) & RTF_HOST))
1713                     rt = NULL;
1714 
1715           if (rt == NULL) {
1716                     /*
1717                      * No matching routes have been found, don't count this
1718                      * as a critical error (here, we set 'error' to 0), just
1719                      * keep moving on, since at least prcloned routes are not
1720                      * duplicated onto each CPU.
1721                      */
1722                     error = 0;
1723           } else {
1724                     rmsg->found_cnt++;
1725 
1726                     rt->rt_refcnt++;
1727                     error = rmsg->callback(rmsg->req, &rtinfo, rt, rmsg->arg,
1728                                               rmsg->found_cnt);
1729                     rt->rt_refcnt--;
1730 
1731                     if (error == EJUSTRETURN) {
1732                               netisr_replymsg(&rmsg->base, 0);
1733                               return;
1734                     }
1735           }
1736 
1737           if (error) {
1738                     KKASSERT(rmsg->found_cnt > 0);
1739 
1740                     /*
1741                      * Under following cases, unrecoverable error has
1742                      * not occured:
1743                      * o  Request is RTM_GET
1744                      * o  The first time that we find the route, but the
1745                      *    modification fails.
1746                      */
1747                     if (rmsg->req != RTM_GET && rmsg->found_cnt > 1) {
1748                               panic("rtsearch_msghandler: unrecoverable error "
1749                                     "cpu %d", mycpuid);
1750                     }
1751                     netisr_replymsg(&rmsg->base, error);
1752           } else {
1753                     if (rmsg->found_cnt == 0) {
1754                               /* The requested route has not been seen ... */
1755                               error = ESRCH;
1756                     }
1757                     netisr_forwardmsg_error(&rmsg->base, mycpuid + 1, error);
1758           }
1759 }
1760 
1761 int
rtmask_add_global(struct sockaddr * mask,boolean_t req_prio)1762 rtmask_add_global(struct sockaddr *mask, boolean_t req_prio)
1763 {
1764           struct netmsg_base msg;
1765           int flags = 0;
1766 
1767           if (req_prio)
1768                     flags = MSGF_PRIORITY;
1769           netmsg_init(&msg, NULL, &curthread->td_msgport, flags,
1770               rtmask_add_msghandler);
1771           msg.lmsg.u.ms_resultp = mask;
1772 
1773           return (netisr_domsg_global(&msg));
1774 }
1775 
1776 struct sockaddr *
_rtmask_lookup(struct sockaddr * mask,boolean_t search)1777 _rtmask_lookup(struct sockaddr *mask, boolean_t search)
1778 {
1779           struct radix_node *n;
1780 
1781 #define   clen(s)   (*(const u_char *)(s))
1782           n = rn_addmask(mask, search, true, rn_cpumaskhead(mycpuid));
1783           if (n != NULL &&
1784               mask->sa_len >= clen(n->rn_key) &&
1785               bcmp((const u_char *)mask + 1,
1786                      n->rn_key + 1, clen(n->rn_key) - 1) == 0) {
1787                     return __DECONST(struct sockaddr *, n->rn_key);
1788           } else {
1789                     return NULL;
1790           }
1791 #undef clen
1792 }
1793 
1794 static void
rtmask_add_msghandler(netmsg_t msg)1795 rtmask_add_msghandler(netmsg_t msg)
1796 {
1797           struct sockaddr *mask = msg->lmsg.u.ms_resultp;
1798 
1799           ASSERT_NETISR_NCPUS(mycpuid);
1800 
1801           if (rtmask_lookup(mask) == NULL) {
1802                     netisr_replymsg(&msg->base, ENOBUFS);
1803                     return;
1804           }
1805           netisr_forwardmsg(&msg->base, mycpuid + 1);
1806 }
1807 
1808 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */
1809 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
1810 
1811 struct rtchange_arg {
1812           struct ifaddr       *old_ifa;
1813           struct ifaddr       *new_ifa;
1814           struct rtentry      *rt;
1815           int                 changed;
1816 };
1817 
1818 static void
rtchange_ifa(struct rtentry * rt,struct rtchange_arg * ap)1819 rtchange_ifa(struct rtentry *rt, struct rtchange_arg *ap)
1820 {
1821           if (rt->rt_ifa->ifa_rtrequest != NULL)
1822                     rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt);
1823           IFAFREE(rt->rt_ifa);
1824 
1825           IFAREF(ap->new_ifa);
1826           rt->rt_ifa = ap->new_ifa;
1827           rt->rt_ifp = ap->new_ifa->ifa_ifp;
1828           if (rt->rt_ifa->ifa_rtrequest != NULL)
1829                     rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt);
1830 
1831           ap->changed = 1;
1832 }
1833 
1834 static int
rtchange_callback(struct radix_node * rn,void * xap)1835 rtchange_callback(struct radix_node *rn, void *xap)
1836 {
1837           struct rtchange_arg *ap = xap;
1838           struct rtentry *rt = (struct rtentry *)rn;
1839 
1840           if (rt->rt_ifa == ap->old_ifa) {
1841                     if (rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) {
1842                               /*
1843                                * We could saw the branch off when we are
1844                                * still sitting on it, if the ifa_rtrequest
1845                                * DEL/ADD are called directly from here.
1846                                */
1847                               ap->rt = rt;
1848                               return EJUSTRETURN;
1849                     }
1850                     rtchange_ifa(rt, ap);
1851           }
1852           return 0;
1853 }
1854 
1855 struct netmsg_rtchange {
1856           struct netmsg_base  base;
1857           struct ifaddr                 *old_ifa;
1858           struct ifaddr                 *new_ifa;
1859           int                           changed;
1860 };
1861 
1862 static void
rtchange_dispatch(netmsg_t msg)1863 rtchange_dispatch(netmsg_t msg)
1864 {
1865           struct netmsg_rtchange *rmsg = (void *)msg;
1866           struct radix_node_head *rnh;
1867           struct rtchange_arg arg;
1868           int cpu;
1869 
1870           cpu = mycpuid;
1871           ASSERT_NETISR_NCPUS(cpu);
1872 
1873           memset(&arg, 0, sizeof(arg));
1874           arg.old_ifa = rmsg->old_ifa;
1875           arg.new_ifa = rmsg->new_ifa;
1876 
1877           rnh = rt_tables[cpu][AF_INET];
1878           for (;;) {
1879                     int error;
1880 
1881                     KKASSERT(arg.rt == NULL);
1882                     error = rnh->rnh_walktree(rnh, rtchange_callback, &arg);
1883                     if (arg.rt != NULL) {
1884                               struct rtentry *rt;
1885 
1886                               rt = arg.rt;
1887                               arg.rt = NULL;
1888                               rtchange_ifa(rt, &arg);
1889                     } else {
1890                               break;
1891                     }
1892           }
1893           if (arg.changed)
1894                     rmsg->changed = 1;
1895 
1896           netisr_forwardmsg(&rmsg->base, cpu + 1);
1897 }
1898 
1899 int
rtchange(struct ifaddr * old_ifa,struct ifaddr * new_ifa)1900 rtchange(struct ifaddr *old_ifa, struct ifaddr *new_ifa)
1901 {
1902           struct netmsg_rtchange msg;
1903 
1904           /*
1905            * XXX individual requests are not independantly chained,
1906            * which means that the per-cpu route tables will not be
1907            * consistent in the middle of the operation.  If routes
1908            * related to the interface are manipulated while we are
1909            * doing this the inconsistancy could trigger a panic.
1910            */
1911           netmsg_init(&msg.base, NULL, &curthread->td_msgport, MSGF_PRIORITY,
1912               rtchange_dispatch);
1913           msg.old_ifa = old_ifa;
1914           msg.new_ifa = new_ifa;
1915           msg.changed = 0;
1916           netisr_domsg_global(&msg.base);
1917 
1918           if (msg.changed) {
1919                     old_ifa->ifa_flags &= ~IFA_ROUTE;
1920                     new_ifa->ifa_flags |= IFA_ROUTE;
1921                     return 0;
1922           } else {
1923                     return ENOENT;
1924           }
1925 }
1926